There are a few areas of evolutionary biology that particularly fascinate me, partly because they represent such a dramatic example of large-scale (macro) evolutionary change. The evolution of whales from terrestrial mammals and of humans from ape ancestors are two of my favorites. But perhaps more dramatic still is the evolution of birds from theropod dinosaurs.

Each discovery of a feathered dinosaur or bird ancestor is a lance straight through the heart of creationist denial of evolution. I have to admit it’s fun to watch prominent creationists squirm when confronted with such clear evidence of transitional forms and evolutionary change – not that they flinch in their denial, but their protestations do become increasingly shrill and desperate.

Welcome Eosinopteryx brevipenna, the latest feathered dinosaur discovered in China. This little guy had feathers, although described as “reduced plumage”, stubby wings (and so was probably flightless), a bony tail, teeth, and clawed fingers. It also lacked many modern bird features, such as bony features that would have allowed for full flapping flight. Its feet were clearly adapted for running.

This creature was not simply a flightless bird, like an ostrich, it was a feathered dinosaur. Minus the feather impressions, in fact, it would look like a typical small theropod dinosaur.

What is increasingly clear from the fossil evidence is that paraves (bird-like theropod dinosaurs) was a diverse and large group, with one path leading to modern birds. It is a beautiful evolutionary story – a bushy tree of adaptive radiation with only one branch surviving into modern times as a definable group – birds.

A century and a half ago biologists hypothesized that birds may have evolved from dinosaurs, a theory that received its first confirming evidence with the discovery of Archaeopteryx in 1860. In the last 30 years paleontologists have discovered numerous species of feathered dinosaurs filling in the morphological space between birds and dinosaurs. They have also discovered that many known theropods, like velociraptor, probably had feathers also, and they have found transitional feathers. It is difficult to imaging a more stunning, thorough, and definitive confirmation of a scientific theory.

Now, one headline described the fossil as “almost birdlike,” and the authors of the report in Nature Communications note many features the fossil shares with living birds, particularly those that live on the ground. In fact, Dr. Elizabeth Mitchell and Dr. David Menton (AiG–U.S.) both examined the photos of the fossil and the criteria the authors used in classifying the fossil as a dinosaur. They agreed that it is a bird, not a feathered dinosaur.

This is a typical creationist tactic – take a continuum in the fossil record, like dinosaurs to birds, and simply claim that any fossil along that continuum belongs to either one end or the other – in this case, is either a dinosaur or a bird. It doesn’t matter that this creature has a pretty even mix of bird and dinosaur features.

Ham continues:

The report claimed that the fossil is between 153 and 165 million years old. Not only that, but the researchers have based all their findings on the assumption that birds are just highly evolved dinosaurs. You see, their whole system of thought is so rooted in evolutionary ideas—like common ancestry—that they can’t see the problems with their own analyses.

Ham does not describe what the alleged problems are. This is another typical creationist tactic, arguing that scientists assume evolution when they analyze fossils, and therefore the fossils are not evidence of evolution. First, these two things are not mutually exclusive. Evolution is proven science, so it is reasonable to take it as a premise. But that does not mean that new evidence interpreted in the context of evolution is not also evidence itself that evolution is correct (as is the case here).

The detailed analysis of Eosinopteryx is anatomical and is independent of evolutionary theory. It has a bony tail and teeth – no matter what you think about the implications of these facts.

I also have to marvel at the irony of Ham accusing scientists of being so “rooted” is a way of thought that they cannot see the obvious (your irony meter definitely needs to go to 11). In fact the next line is:

The fossil record doesn’t reveal any kind of dinosaur-to-bird evolution—and it certainly does not show a molecules-to-man evolution. We have no proof of transitional forms, and we won’t. God’s Word says clearly that He created animals and plants according to their kinds (Genesis 1).

I see, we will never have proof of transitional forms because the bible tells us so. In other words – no matter how much stunning and incontrovertible evidence we discover of transitional forms, believers in Ham’s version of reality simply cannot see it – must not see it.

What Eosinopteryx proves is that dedicated creationists will not acknowledge transitional forms no matter how solid the proof. If Eosinopteryx is not a transitional form – then what is? What could possibly qualify as a transitional form in Ham’s eyes. Perhaps he adheres to the crocoduck school of creationist thought – only an impossible chimera (something not predicted by evolutionary theory) would be evidence of evolution. That’s a nice way to rig the game.

Ham links to an allegedly more detailed analysis by Elizabeth Mitchell, but her analysis contains almost no new details, and is just more wordy. She discusses the report in more detail, and her only counter point is the same claim that scientists assume evolution in their classification scheme. She thinks the fossil is a bird, and does not address the teeth, bony tail, clawed fingers, and other obvious dinosaur features.

Conclusion

Scientists have uncovered increasing examples of feathered dinosaurs and creatures that are morphologically transitional from dinosaurs to birds. This is not a straight line or “ladder”, but a diverse bush. The evidence is now overwhelming. Creationists are reacting with the intellectual equivalent of sticking their fingers in their ears and droning “I can’t hear you.” They maintain their increasingly bizarre claim that there are no transitional fossils (because there just can’t be).

This is clear evidence of both the power of evolutionary theory and the intellectual bankruptcy of creationism.

16 Responses to “Transition Denial and Feathered Dinosaurs”

I’m curious as to the actual definition of transitional fossil is. Now if this dinosaur was just an evolutionary dead end, and perhaps was the last species in its family is this not a transitional fossil?

slip – you are right to question the definition of transitional fossil. In reality, all fossils are transitional. What is meant, though, is a fossil species that fills the morphological space between two other species or taxonomic groups. This could be between two extant groups, or an ancestor and descendant. The transitional species does not have to be exactly on the line leading to a descendant group, but can be closely related.

Not really because chimps and humans are equidistant from monkeys (so they are not between us and monkeys). Chimps are transitional between humans and other apes (by a little). Homo erectus is transitional between humans and our common ancestor with other apes. Monkeys are transitional between humans and other mammals.

If you graph it out the transitional species will have to be somehow between the two other species or groups between which they are transitional.

And to be clear – don’t confuse “transitional species” with “transitional fossils.” A transitional species can be extinct or extant, a transitional fossil is known from fossil evidence.

Suppose I should have just asked what I was really thinking. Just trying to relate the little fossil knowledge we have of dinosaurs to what some new species would see with humans and chimps in a couple million years if they had gone extinct. I could see how they would see monkeys, humans, and then a chimp may fit as the transitional piece, even though we today know chimps are not. But are more of a cousin to humans.

By Ken Ham’s reasoning, an infant could ever become an adult because there is no point at which you could say that the infant has become a child, the child has become an adolescent, or the adolescent has become an adult.

This right here is the source of Ken’s frustration and the reason he rails against evolution. The terrifying idea that humans are not special, pure little snowflakes.

It would be fun to teach him what the human body is actually made of (mostly oxygen apparently) with close ups of all the germs smothering his body and the air he breathes and an explanation of how much humans in fact rely on such bacteria to survive.

I think we could have him sobbing in the fetal position in about 10 minutes.

And for something so pointless. It’s one thing if it mattered, ie that there was some actual public policy imperative he was furthering (eg as his ilk typicaly do re their anti-safe abortion agenda), but here, the very best he can hope for is that his ridiculous gibberish is incorporated into some textbooks in one corner of the world (the USA or a subset thereof), while science ticks on regardless across the rest of the world and, indeed, in the wheeling wonder of the universe itself.

Seriously, I ask myself, what does this fellow hope to achieve? To prove that God favours the foolish?
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The need to believe in the special status of humans runs deep, apparently. If we’re not made in the image of god, then human consciousness must be something so unfathomably magnificent it must be the fabric of the universe.

@Davdoodles:

Our core beliefs are not subject to rational scrutiny. It seems the more unblievable they are (to a disinterested third party), the easier it is for the mind to reject rational arguments against them.

This all reminds me of the Monty Python sketch Parrot Sketch, although the point here is that ‘this is no dead parrot’. (come on, read it with John Cleese’ voice)

I mean honestly, how daft are they? Any nine-year-old can tell you that is no beak. If I was a creationist I would argue, that what appears to be feathers is actually something else, like fossilized leaves or something and say that it’s just a regular dinosaur. But to ague that this is a bird…

Yes, evolution make humans less special, but there’s more to Ken Ham’s motivation.

Evolution-denial has a very special place in Christianity. To be Christian is to believe “Jesus died for our sins”. In many of the evolutionary branches of Christianity, those “sins” are the result of Adam and Eve defying God’s rules re the fruit of the tree of knowledge of good and evil.

No evolution, no Adam and Eve and Garden of Eden. No Adam and Eve, no Original Sin. No Original Sin, no explanation for why Jesus had to die for our sins. No reason for Jesus, no reason for the religion.

For people who think the Bible is journalism (as opposed to poetry), who think it is a textbook (as opposed to metaphor), evolution destroys the tenuous logic of their faith.

I’m sure you know all this. Forgive me for stating the obvious, but I couldn’t resist. Typing it all out is an entertaining reminder of the fragile absurdity of the whole Jesus/sin construct.

The creationist position on this highlights a problem generally with taxonomic nomenclature. The argument that “this is just a bird” (or, that “this is just a dinosaur”) is only available because we linguistically distinguish between the two with a bright line, whereas in reality the two shade into each other. In day to day English, “birds” and “dinosaurs” are seen as conceptually different things, even though in reality the former is merely a subset of the former.

Unless we develop a word that becomes accepted generally as meaning “non-avian dinosaurs and birds together as a single clade” then creationists will always be able to hide behind this linguistic divide, no matter how ludicrously, to claim that there are birds and there are dinosaurs and the two are not related.

However, there is a simple way to expose the flaw in the creationist position. First, compile a list of creationist “experts”. Secondly, arrange as complete a set as possible of fossils ranging from dinosaurs with the merest hint of feathering, through to birds with the last vestiges of terrestrialism (the extant, clawed Hoatzin chick for example) including all the dead end lineages. Thirdly, ask the experts to each independently assign the fossils as either “birds” or “dinosaurs”. I am willing to bet that no two “experts” would draw the line between the two in the same place. Even if they all agreed, and stated the reasons for classifying the fossils one way or another, eventually a fossil would be found that was unclassifiable using those same reasons.